The
list that follows has been based on material extracted from the Deutsches
Reichs-Addressbuch (several editions, 1900 to 1942);
from Solingen und Sein Industriebezirk (published in 1922); Rasierklingen-Code
(1932); Cutlery & Flatware, Made in Germany (1983); and the Adressbuch
der Stadt Solingen for several years between 1892 and 1989.

The
entries are currently based only on evidence gathered from the categories 'Rasierapparatefabrik'
('safety-razor maker'), 'Raiserklingenfabrik' ('razor-blade maker'), 'Rasiermesserfabrik'
('open-blade razor maker') and 'Taschenmesserfabrik' ('pocket-knife maker'); the lists of blade-forgers and grip makers have also been consulted.

A start has been made on linking manufacturers with individual brand names, and, in particular, to provide a date of registry for each mark. This is not easy: it is likely to be some time before the work is completed, particularly as the knife- and razor makers represent only one specific part of the cutlery and toolmaking industry. In addition, accessible sources of trademark information (despite the on-line research facilities offered by the Deutsches Patentamt, http://www.dpma.de) are few and far between.

Many details have been provided by the Warenzeichenblatt of 1904 and Fabrik- und Waren-Zeichen, published in six volumes in 1924–6, but gaps in coverage remain. In addition, Fabrik- und Waren-Zeichen does not provide dates for each mark—merely the registration number. This problem has been largely resolved by the creation of a number/date correlator, which has proceeded through several improvements until it can predict the date of registry with an accuracy of '± one year'. A few problems remain, however, largely owing to the comparative lack of material surviving from the pre-1919 period; and they are usually most obvious at the beginning and end of each year. Consequently, dates given below as '1919–20' suggest that the mark originated between 1st January 1919 and 31st December 1920; '1919/20', however, suggests that registry was confined to the few weeks either side of New Year's Day 1920.

Sudden spurts of enthusiasm for trademarks and brand names occurred in the late 1890s, when a new law was enacted; in the early 1900s, when strenuous attempts to increase exports were made; immediately after the end of the First World War, when a rapid rise in the creation of small manufactories was evident in 1919–20; and in the late 1920s, before the Wall Street Crash of 1929, when the importance of safety razors and replaceable blades became universally appreciated. Understandably fewer claims were registered during the First World War, and in the economically disastrous early 1930s.

Some marks stood the test of time, but many remained fashionable only for short periods. This was particulary true of those that celebrated specific events or personality: for example, 'Admiral Dewey' honoured the victor of the Battle of Santiago during the Spanish-American War of 1898 and 'Culebra Cut' marked completion of the final stages of the construction of the Panama Canal.

It is also important to remember that, with the comparatively few exceptions of large conglomerates, the toolmaking industry centred on Remscheid and the cutlery-making industry of Solingen were surprisingly fragmented. Extensive use was made of outworkers. According to statistics gathered in 1938, Pfeilring-Werke employed 143 people 'on site' and 53 Heimarbeiter ('home-workers'); and the J.A. Henckels workforce numbered 1201 inside the factory gates, with 144 more working in their homes. Many of the smaller 'manufacturers' of knives and razors listed below were little more than assemblers of parts made elsewhere.

Brand names and trademarks were usually registered for a period of ten years, which could allow unexpected changes of ownership when renewal was required. Some changed hands when fathers passed businesses to sons or sons-in-law; when partnerships ceased; when individual metalsmiths retired; or when amalgamations took place. And there are many cases, arising from a comparatively loose registry process, where several grants of the same mark or name could be made simultaneously…even in the same registry class! This can complicate the identification process unnecessarily.

In addition to changes arising from the 'natural causes' mentioned previously, disappearance of some workshops and manufactories was due to the devastating air-raids undertaken by the Royal Air Force on Remscheid during the night of 30th/31st July 1943 and on Solingen on 4th and 5th November 1944. Large areas of the Altstädte, the historic 'Old Towns', were reduced to rubble. The death-toll in Remscheid was at least 1063, and 194 of a total of about seven hundred businesses were affected: 107 ('mostly small workshops') were totally destroyed. In Solingen, where about 1700 were killed, more than 1600 dwellings were destroyed and 13,000 people, including many tradesmen, immediately left the area. The Second World War was a blow from which many businesses were never to recover.